Mash all the bananas in a blow of mixer using paddle attachment. Add brown sugar, oil, egg and vanilla extract. Beat until smooth. Then add flours, baking powder, baking soda, salt and sour cream. Mix until combine. Don't over do it.

STEP3

Fill muffin pan all the way to the top and garnish with blueberries. Bake in muffin pans for about 25mins or try to insert tester stick in to the center and it comes out clean. Let them cool on wire rack. Serve at room temperature.